This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Urea Deposit Predictions on a Practical Mid/Heavy Duty Vehicle After-Treatment System
Technical Paper
2018-01-0960
ISSN: 0148-7191, e-ISSN: 2688-3627
This content contains downloadable datasets
Annotation ability available
Sector:
Language:
English
Abstract
Urea/SCR systems have been proven effective at reducing NOx over a wide range of operating conditions on mid/heavy duty diesel vehicles. However, design changes due to reduction in the size of modern compact Urea/SCR systems and lower exhaust temperature have increased the possibility of urea deposit formation. Urea deposits are formed when urea in films and droplets undergoes undesirable secondary reactions and generate by-products such as ammelide, biuret and cyanuric Acid (CYA). Ammelide and CYA are difficult to decompose which lead to the formation of solid deposits on the surface. This phenomenon degrades the performance of the after treatment system by decreasing overall mixing efficiency, lowering de-NOx efficiency and increasing pressure drop. Therefore, mitigating urea deposits is a primary design goal of modern diesel after-treatment systems. The purpose of current study is to introduce the Computational Fluid Dynamics (CFD) approach to predict urea deposit formation in the Isuzu exhaust system using detailed urea decomposition mechanism. Conjugate Heat Transfer (CHT) is used along with the advanced splashing and film evaporation models to correctly predict the film temperature. Detailed decomposition mechanism approach with a modified multi component evaporation model was used to capture the urea deposit production process. The results were compared against engine dyno test data for mass accumulation prediction and gas-chromatograph (GC) - QTOFMS results for urea deposit chemical component prediction.
Recommended Content
Authors
Topic
Citation
Sun, Y., Sharma, S., Vernham, B., Shibata, K. et al., "Urea Deposit Predictions on a Practical Mid/Heavy Duty Vehicle After-Treatment System," SAE Technical Paper 2018-01-0960, 2018, https://doi.org/10.4271/2018-01-0960.Data Sets - Support Documents
Title | Description | Download |
---|---|---|
Unnamed Dataset 1 |
Also In
References
- Yim , S.D. , Kim , S.J. , Baik , J.H. , Nam , I.-S. et al. Decomposition of Urea into NH3 for the SCR Process Industrial & Engineering Chemistry Research 43 4856 4863 2004 10.1021/ie034052j
- Lundström , A. , Andersson , B. , and Olsson , L. Urea Thermolysis Studied under Flow Reactor Conditions Using DSC and FTIR Chemical Engineering Journal 150 2-3 544 550 2009 10.1016/j.cej.2009.03.044
- Ebrahimian , V. , Nicolle , A. , and Habchi , C. Detailed Modeling of the Evaporation and Thermal Decomposition of Urea-Water Solution in SCR Systems AICHE Journal 58 7 1998 2009 2012 10.1002/aic.1273
- Munnannur , A. , Chiruta , M. , and Liu , Z. Thermal and Fluid Dynamic Considerations in Aftertreatment System Design for SCR Solid Deposit Mitigation SAE Technical Paper 2012-01-1287 2012 10.4271/2012-01-1287
- Xu , L. , Watkins , W. , Snow , R. , Graham , G. et al. Laboratory and Engine Study of Urea-Related Deposits in Diesel Urea-SCR After-Treatment Systems SAE Technical Paper 2007-01-1582 2007 10.4271/2007-01-1582
- Nishioka , A. , Sukegawa , Y. , Katogi , K. , Mamada , H. et al. A Study of a New Aftertreatment System (2): Control of Urea Solution Spray for Urea-SCR SAE Technical Paper 2006-01-0644 2006 https://doi.org/10.4271/2006-01-0644
- Zheng , G. , Fila , A. , Kotrba , A. , and Floyd , R. Investigation of Urea Deposits in Urea SCR Systems for Medium and Heavy Duty Trucks SAE Technical Paper 2010-01-1941 2010 10.4271/2010-01-1941
- Dong , H. , Shuai , S. , and Wang , J. Effect of Urea Thermal Decomposition on Diesel NOx-SCR Aftertreatment Systems SAE Technical Paper 2008-01-1544 2008 10.4271/2008-01-1544
- Strots , V. , Santhanam , S. , Adelman , B. , Griffin , G. et al. Deposit Formation in Urea-SCR Systems SAE Int. J. Fuels Lubr. 2 2 283 289 2010 10.4271/2009-01-2780
- Kontin S. , Höfler A. , Koch R. , and Bauer H.J. Heat and Mass Transfer Accompanied by Crystallisation of Single Particles Containing Urea-Water Solution, ILASS-Europe 2010 23rd Annual Conference on Liquid Atomization and Spray Systems Brno 2010
- Birkhold , F. , Meingast , U. , Wassermann , P. , and Deutschmann , O. Modeling and Simulation of the Injection of Urea-Water-Solution for Automotive SCR DeNOx-Systems Applied Catalysis B: Environmental 70 119 127 2007
- Reinhold , M. 2001
- Abu-ramadan E. , Saha , K. , and Li X. Modeling the Depleting Mechanism of Urea-Water-Solution Droplet for Automotive Selective Catalytic Reduction Systems AICHE Journal 10.1002/aic.12523,2011
- Eichelbaum , M. , Farrauto , R.J. , and Castaldi , M.J. The Impact of Urea on the Performance of Metal Exchanged Zeolites for the Selective Catalytic Reduction of NOxPart I. Pyrolysis and Hydrolysis of Urea over Zeolite Catalysts Applied Catalysis B: Environmental 97 1-2 90 97 2010
- Munnannur , A. and Liu , Z.G. Development and Validation of a Predictive Model for DEF Injection and Urea Decomposition in Mobile SCR DeNOx Systems SAE Technical Paper 2010-01-0889 2010 10.4271/2010-01-0889
- Abu-Ramadan , E. , Saha , K. , and Li , X.G. Modeling of the Injection and Decomposition Process of Urea-Water-Solution Spray in Automotive SCR systems SAE Technical Paper 2011-01-1317 2011 10.4271/2011-01-1317
- Schaber , P.M. , Colson , J. , Higgins , S. , Thielen , D. et al. Thermal Decomposition (Pyrolysis) of Urea in an Open Reaction Vessel Thermochimica Acta 424 131 142 2004
- Habchi , C. , Nicolle , A. , and Gillet , N. Numerical Study of Urea-Water Solution Injection and Deposits Formation in an SCR System ICLASS 2015, 13th Triennial International Conference on Liquid Atomization and Spray Systems Tainian 2015
- Brack , W. , Heine , B. , Birkhold , F. , Kruse , O. et al. Emission Control Science and Technology 2 115 2016 https://doi.org/10.1007/s40825-016-0042-2
- Richards , K.J. , Senecal , P.K. , and Pomraning , E. CONVERGE (2.4) Madison Convergent Science, Inc. 2017
- Senecal , P. , Richards , K. , Pomraning , E. , Yang , T. et al. A New Parallel Cut-Cell Cartesian CFD Code for Rapid Grid Generation Applied to In-Cylinder Diesel Engine Simulations SAE Technical Paper 2007-01-0159 2007 10.4271/2007-01-0159
- Rhie , C.M. and Chow , W.L. Numerical Study of the Turbulent Flow Past an Airfoil with Trailing Edge Separation AIAA Journal 21 11 1525 1532 1983 10.2514/3.8284
- Senecal , P.K. , Pomraning , E. , Richards , K. , and Som , S. Grid Convergent Spray Models for Internal Combustion Engine CFD Simulations Proceedings of the ASME 2012 Internal Combustion Engine Division Fall Technical Conference, ICEF2012-92043 Vancouver 2012
- Kuhnke , D. 2004 3-3822-3539
- Richards , K.J. , Senecal , P.K. , and Pomraning , E. CONVERGE (Version 2.4) Manual Madison Convergent Science, Inc. 2017
- Zheng , G. , Zhang , S. , Wang , F. , Liu , Z. et al. Design Optimization of an Integrated SCR System for EU V Heavy Duty Diesel Engines SAE Technical Paper 2016-01-0945 2016 10.4271/2016-01-0945
- Smith , H. , Lauer , T. , Mayer , M. , and Pierson , S. Optical and Numerical Investigations on the Mechanisms of Deposit Formation in SCR Systems SAE Int. J. Fuels Lubr. 7 2 525 542 2014 10.4271/2014-01-1563
- Zhang , H. , Xi , Y. , Su , C. , and Liu , Z. Lab Study of Urea Deposit Formation and Chemical Transformation Process of Diesel Aftertreatment System SAE Technical Paper 2017-01-0915 2017 10.4271/2017-01-0915